使用改良半固定桥修复单个缺失后牙的3年临床观察

Three-year clinical effects of a modified semi-fixed bridge on restoring a missing posterior tooth

目的:观察一种改良半固定桥(使用金属翼板和全冠作为固位体,其中桥体与金属翼板间使用非刚性连接体)修复单个缺失后牙的临床修复效果。方法:在临床上选择38例单个后牙缺失患者,要求1个基牙牙体缺损较大,另1个基牙牙体完整。在牙体完整的基牙上使用金属翼板固位体,在其邻近缺隙侧放置栓体;另1个基牙用全冠作为固位体,与桥体刚性连接,在桥体的另一侧放置栓道,与金属翼板上的栓体形成非刚性连接。同时选取42例相同条件的病例,使用传统双端固定桥进行修复。对比改良半固定桥与传统双端固定桥修复单个缺失后牙的效果。结果:改良半固定桥组平均观察时间为40.3个月(最短观察时间9个月,最长60个月),其中有1例在使用7个月后、1例在使用20个月后,全冠固位体和桥体一侧发生松动脱落,其余未出现异常。对照组平均观察时间为44.7个月(最短22个月,最长50个月),未发现基牙松动、固位体松动等。所有80例修复体边缘良好,基牙均没有出现龋坏及基牙松动等情况。结论:改良半固定桥在观察期内显示出良好的修复效果,该方法一侧采用金属翼板固位体,有利于保留健康牙体组织,是一种简单易行的修复方法。

Objective:To observe the effects of a modified semi-fixed bridge to restore a missing posterior tooth for three years.Methods:In the study,38 cases with a posterior tooth missed were chosen as experiment group.The inclusion criteria for these cases required that one abutment tooth be defected,and another abutment intact.The missed posterior tooth was restored with a modified semi-fixed bridge in which a metal wing retainer was applied to the intact abutment tooth and a full crown retainer was applied to the defected abutment tooth,and the non-rigid connector linked to the metal wing retainer and the pontic,while the rigid connector linked to the full crown retainer and the pontic.And 42 cases with same abutment conditions were chosen as control group.These control patients were treated with classical rigidly-fixed partial dentures.The clinical effects regarding the bridge survival,abutment conditions,and etc.were observed by examination.Results:The average observation time for experiment group was 40.3 months(from 9 to 60 months).One case failed with loose crown retainer after 7 months’usage.Another failed case was the same performance after 20 months’wearing.The restorations were rebounded after the inner face of crowns was treated,and they were used normally.No loose abutment and retainer,no decayed abutment teeth were found,and the marginal adaptations between retainers and abutment teeth were good.The average observation time of control group was 44.7 months(from 22 to 50 months).No secondary decays and loose abutment teeth were detected and the marginal adaptation of the retainers was good.Conclusion:This modified semi-fixed bridge has similar survival rate and clinical effects to restore a missing posterior tooth when compared with the traditional rigidly-fixed partial dentures.But the long-term observation is required.